Answer:
An amino acid activates the repressor so that the repressor binds to the operator and prevents transcription.
Explanation:
In an operon, promoter is followed by operator which is finally followed by the structural genes to be transcribed. RNA Polymerase binds to the promoter and initiates transcription. A repressor can negatively control the transcription process by binding to the operator so that the RNA Polymerase is not able to move forward and transcription is halted.
For example: in trp operon, tryptophan amino acid binds to the repressor molecule which leads to change in repressor's shape. The repressor is now able to bind to the operator and prevent transcription.
Once you have stopped for a school bus, do not pass until the driver signals you to proceed, the red lights stop flashing, or the bus starts moving ahead. Whenever a vehicle ahead of you stops to let a pedestrian pass in front of you, you should stay in line and until the vehicle ahead proceeds.
Below are the 6 reasons a bone must be continually remodeled:
1.new cancellous bone must be remodeled into compact bone tissue.
2.bones increase and decrease in mass based on the stress they experience.
3.reshape the bone.
4.rapair the bone.
5.remodeled to replace worn collagen and hydroxyapatite.
<span>6.regualate calcium levels in the blood.</span>
Contaminated water such as polluted water can sometimes cause an explosion of new plant growth by providing necessary nutrients and food and at other times it can kill or harm plants such as by raising or lowering acidity. Plants need at least good levels of potassium, nitrogen and phosphorus for healthy growth and by corollary, biodiversity. I believe that water which contains these elements, even if it be contaminated with the right contaminants will aid in biodiversity by enhancing growth. On the other hand, if there is too much salt, for example in the water it will prevent growth and inhibit photosynthesis.